#ifndef SHARE_VM_ADLC_ARENA_HPP
#define SHARE_VM_ADLC_ARENA_HPP

// All classes in adlc may be derived
// from one of the following allocation classes:
//
// For objects allocated in the C-heap (managed by: malloc & free).
// - CHeapObj
//
// For classes used as name spaces.
// - AllStatic
//

class CHeapObj {
public:
    void *operator new(size_t size) throw();

    void operator delete(void *p);

    void *new_array(size_t size);
};

// Base class for classes that constitute name spaces.

class AllStatic {
public:
    void *operator new(size_t size) throw();

    void operator delete(void *p);
};

//------------------------------Chunk------------------------------------------
// Linked list of raw memory chunks

class Chunk : public CHeapObj {

private:

    // This ordinary operator delete is needed even though not used, so the
    // below two-argument operator delete will be treated as a placement
    // delete rather than an ordinary sized delete; see C++14 3.7.4.2/p2.
    void operator delete(void *p);

public:
    void *operator new(size_t size, size_t length) throw();

    void operator delete(void *p, size_t length);

    Chunk(size_t length);

    enum {
        init_size = 1 * 1024, // Size of first chunk
        size = 32 * 1024 // Default size of an Arena chunk (following the first)
    };

    Chunk *_next; // Next Chunk in list
    size_t _len; // Size of this Chunk

    void chop(); // Chop this chunk

    void next_chop(); // Chop next chunk

    // Boundaries of data area (possibly unused)
    char *bottom() const { return ((char *) this) + sizeof(Chunk); }

    char *top() const { return bottom() + _len; }
};

//------------------------------Arena------------------------------------------
// Fast allocation of memory

class Arena : public CHeapObj {
protected:
    friend class ResourceMark;

    friend class HandleMark;

    friend class NoHandleMark;

    Chunk *_first; // First chunk
    Chunk *_chunk; // current chunk
    char *_hwm, *_max; // High water mark and max in current chunk

    void *grow(size_t x); // Get a new Chunk of at least size x

    size_t _size_in_bytes; // Size of arena (used for memory usage tracing)
public:
    Arena();

    Arena(size_t init_size);

    Arena(Arena *old);

    ~Arena() { _first->chop(); }

    char *hwm() const { return _hwm; }

    // Fast allocate in the arena.  Common case is: pointer test + increment.
    void *Amalloc(size_t x) {
#ifndef _LP64
        x = (x + (8 - 1) & ((unsigned) (-8)));
#else
        x = (x + (4 - 1)) & ((unsigned) (-4));
#endif
        if (_hwm + x > _max) {
            return grow(x);
        } else {
            char *old = _hwm;
            _hwm += x;
            return old;
        }
    }

    // Further assume size is padded out to words
    // Warning:  in LP64, Amalloc_4 is really Amalloc_8
    void *Amalloc_4(size_t x) {
        assert((x & (sizeof(char *) - 1)) == 0, "misaligned size");
        if (_hwm + x > _max) {
            return grow(x);
        } else {
            char *old = _hwm;
            _hwm += x;
            return old;
        }
    }

    // Fast delete in area.  Common case is: NOP (except for storage reclaimed)
    void Afree(void *ptr, size_t size) {
        if (((char *) ptr) + size == _hwm) _hwm = (char *) ptr;
    }

    void *Acalloc(size_t iterms, size_t x);

    void *Arealloc(void *old_ptr, size_t old_size, size_t new_size);

    // Reset this Arena to empty, and return this Arenas guts in a new Arena.
    Arena *reset(void);

    // Determine if pointer belongs to this Arena or not.
    bool containes(const void *ptr) const;

    // Total of all chunks in use (not thread-safe)
    size_t used() const;

    // Total # of bytes used
    size_t size_in_bytes() const { return _size_in_bytes; }

    void set_size_in_bytes(size_t size) { _size_in_bytes = size; }
};

#endif // SHARE_VM_ADLC_ARENA_HPP